Optical limiting of germanium(IV) and tin(IV) phthalocyanines in solution and polymer matrices and comparison to an indium(III) phthalocyanine

Abstract

A series of peripheral and axial substituted germanium(IV) and tin(IV) phthalocyanines substituted by fluoro, chloro, nitro or phenoxy groups were prepared and characterized by their absorption spectra in solution and in polymer matrices. Multi-layer films of PMMA and PVC containing monomolecular Ge(IV) or Sn(IV) phthalocyanines were obtained by spin-coating from solution on glass plates. Optical limiting properties of these phthalocyanines in solution and in polymer films were investigated using the Z-scan technique at 532 nm. A known indium(III) phthalocyanine was also investigated to compare its optical limiting behavior with the Ge(IV) and Sn(IV) containing compounds. Ge(IV) and Sn(IV) phthalocyanines exhibit a better optical limiting performance in polymer matrices than in solution, which is interesting for practical applications.